In this work, we report for the first time on the influence of the quality of reactants and reaction conditions on the production of hydrophobically modified ethoxylated urethanes (HEURs) and selected prepolymers without the use of solvents. We show that the polyol water concentration is detrimental to the progress of the main urethane forming reaction, confirming the necessity of carefully drying the reactants below 1000 ppm to suppress the consumption of diisocyanate toward urea during HEUR synthesis. Increasing the mixing speed (≈30 to 750 rpm), reaction temperature (80−110 °C), and catalyst concentration (0.035−2.1 wt % bismuth carboxylate) can significantly increase the rate of molecular weight buildup, but their effect decreases with time as the bulk viscosity increases and mixing limitations eventually take over, leading to the Weissenberg effect and chain growth termination. Consequently, for the selected formulation, the maximum product molecular weight attained lies in the range of ≈20 000−22 000 g/ mol, irrespective of the specific process conditions applied.

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In this paper, a novel method for mobile terminal (MT) subarea localisation in GSM networks is presented. No base stations position and additional hardware are required. It is a variation of the fingerprinting localisation method aiming to determine not the MT geographic position but the MT subarea and to reduce necessary initialisation measurements. Several GSM-based methods have been developed for MT localisation.The localisation method, proposed in this paper, is based on the fingerprinting method but is differentiated regarding the produced result. In this method the location server does not compare the MT collected radio network measurements with the stored radio map but with the subareas proprietary characteristics indicating the subarea where the MT is located and not the exact MT geographic position. Finally, if an LBS requires as input the subscriber subarea and not the geographic position then the novel method presented here reduces significantly the localisation initialisation requirements and computational cost in order to provide the service.